Struct BetaCounters 

pub struct BetaCounters {
    pub alpha: u32,
    pub beta: u32,
}

A detector’s running Beta posterior counters. Always ≥1 each (Beta(1,1) uniform prior baseline) to avoid posterior_mean undefined when a detector has had no observations yet.

Fields

alpha: u32

beta: u32

Implementations

impl BetaCounters

pub fn posterior_mean(&self) -> f64

Posterior mean: α / (α + β). Falls in [0, 1]; the higher, the more reliable the detector is historically.

This is the single canonical implementation. The scanner confidence pipeline and the keyhog calibrate --show UI both call this method rather than re-deriving the arithmetic, so the three crates can never drift apart.

pub fn observations(&self) -> u32

Number of observations (excluding the prior) the posterior is built on. Useful for “trust the recent history” UI gates.

kimi-confidence audit: the previous form was alpha.saturating_sub(1) + beta.saturating_sub(1) - the + was a plain add and would panic in debug / wrap to 0 in release once both counters reached ~u32::MAX / 2. Use saturating_add so the result clamps at u32::MAX instead of wrapping. That’s still a frozen counter at saturation, but the posterior mean stays correct and no detector silently gets disabled.

Public for the same single-source-of-truth reason as BetaCounters::posterior_mean: the scanner observation gate and the CLI --show table share this one implementation.

Trait Implementations

impl Clone for BetaCounters

fn clone(&self) -> BetaCounters

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for BetaCounters

impl Debug for BetaCounters

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for BetaCounters

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for BetaCounters

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for BetaCounters

impl PartialEq for BetaCounters

fn eq(&self, other: &BetaCounters) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for BetaCounters

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for BetaCounters